Function prime_blocking 

pub async fn prime_blocking(
    state: &Arc<AppState>,
    clock: &ClockHandle,
) -> Result<bool>

Synchronous startup prime. Called by server::serve before the listener opens so routes that read state.verified_fleet (e.g. channel_status, the enrollment route’s freshness check) see a populated snapshot on the first request.

Returns Ok(false) when no channel_refs_source is configured (test + offline boot paths fall back to prime_from_artifact_files).